Healthy Community Planning - What's It Worth?

We live in a wonderful age! Scientists have proven that many simple, affordable, and often enjoyable activities make us healthier and happier: breath fresh air, avoid dangerous driving, be physically active, eat fresh fruits and vegetables, maintain friendships, play games, and avoid excessive stress. Even chocolate, red wine and sex are perscribed, in moderation, for health sake.

We live in a wonderful age! Scientists have proven that many simple, affordable, and often enjoyable activities make us healthier and happier: breath fresh air, avoid dangerous driving, be physically active, eat fresh fruits and vegetables, maintain friendships, play games, and avoid excessive stress. Even chocolate, red wine and sex are perscribed, in moderation, for health sake.

One of the most effective public health strategies is to encourage active transportation (walking, cycling, and variants such as roller skating). Although I've worked on this issue for years, I did not fully appreciate the magnitude of these benefits until a couple weeks ago when I participated in a special workshop sponsored by the U.S. Center For Disease Control and Prevention to produce a U.S. version of the Health Economic Assessment Tool (HEAT), a science-based computer model developed by the World Health Organization that calculates the value of health benefits of increased cycling activity. Eventually, we plan to expand it to also include walking health benefits.

This workshop brought together leading researchers on this subject from around the world. (One evening we celebrated our international collaboration by sampling beers from each other's countries at a local bar, but there were far too many to drink in one sitting.) I learned a lot. Current research indicates that regular doses of moderate physical activity provide these benefits:

50% reduction in the risk of developing coronary heart disease (similar to not smoking).

50% reduction in the risk of becoming obese.

50% reduction in the risk of developing adult diabetes.

30% reduction in the risk of developing hypertension

For people with hypertension, blood pressure reductions comparable to costly drugs

20% reduction in common forms of cancer (breast and colon)

Helps to maintain bone mass and so protects against osteoporosis

Improves balance, coordination, mobility, strength and endurance.

Relieve symptoms of depression and anxiety, and increases self-esteem and overall psychological wellbeing.

"On average, it appears that compared to less than 0.5 hour per week of moderate-to-vigorous physical activity, engaging in approximately 1.5 hours per week of such activity is associated with about a 20% reduction in risk of all cause mortality. Additional amounts of physical activity are associated with additional risk reductions, but at smaller magnitudes, such that an additional approximately 5.5 hours per week are required to observe a further 20% decline in risk (i.e., approximately 7.0 hours per week is associated with approximately 40% reduction in risk, compared with less than 0.5 hour per week)."

This figure from the Physical Activity Guidelines For Americans report shows the reductions in mortality caused by increases in physical activity. These studies suggest that 15 daily minutes of brisk walking or cycling reduces the risk of dying by 20%, and 60 daily minutes reduces this risk by 40%.

The U.S. currently lags the OECD average lifespan by about one year. This poor health performance can largely be explained by high rates of automobile-dependency, which cause high rates of traffic fatalities and diseases associated with sedentary living, compared with peer countries. Described more positively, transportation and land use planners can help imporve public health and reduce medical costs by creating more walkable and bikable communities, so more people achieve their twenty daily minutes of moderate physical activity during normal local travel.

More active transportation can provide huge savings in lives, disability costs and healthcare expenses. Some recent studies have quantified and monetized (measured in monetary units) these benefits, suitable for use in transportation planning:

Boarnet, Greenwald and McMillan (2008) developed a framework for valuing the health benefits of urban design improvements that increase walking activity. They estimated the monetized benefits of improving neighborhood walkability in a typical neighborhood.

A study titled, The Impact of the Green Transport Mode on Public Health Improvement by the Korea Transport Institute found that commuters who switching from automobile to walking or cycling for eight weeks experienced significantly reduced lower blood pressure, improved lung capacity, and improved cholesterol counts. It estimated that commuters who use active modes achieve annual health and fitness benefits worth an average of 2.2 million Korean Won (about $2,000). They found that incorporating these values into transport project evaluation significantly affected outcomes.

Land Transport New Zealand's Economic Evaluation Manual provides monetary values for the health benefits of active transportation resulting from planning decisions that increase walking or cycling activity. It estimates that each additional kilometer of cycling is worth 16¢ and each additional kilometer of walking is worth 40¢ in health benefits. Half of these benefits are internal to the people who increase their physical activity, and half are external benefits to society due to medical cost savings.

Guo and Gandavarapu (2010) identify various geographic, demographic and urban design factors that tend to increase walking and cycling, and reduce automobile travel. They find that the provision of sidewalks significantly increases walking activity, and use a simple model to evaluate the cost effectiveness of neighborhood sidewalk construction based on health and air pollution reduction benefits.

This research indicates that health benefits are large compared with other planning objectives, but they tend to be overlooked in conventional transport economic evaluation. A transportation policy or project is worth far more than generally recognized if it increases walking and cycling activity, and far less if it reduces walking and cycling. This has important implications for decisions such as roadway design, traffic calming, investments in sidewalks and paths, and land use policies that affect the amount of nonmotorized travel that occurs in a community.

Health Economic Assessment Tool (HEAT)for cycling is a science-based computer model developed by the World Health Organization that calculates the human health benefits that result from increased cycling activity (http://euro.who.int/transport/policy/20081219_1).

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